Sprockets & Gearing issues

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simplex
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Hi
I had a standard DL125 gearbox 15/46 with a 175 head .. didnt really get on with it..i would be in 4th within a few metres.. bit rubbish for the daily commute with a mixture of town and country... i have changed this to 18/47 .. a bit sluggish at the lights - ok through 2nd & 3rd and cant really cope with any incline in 4th unless I have a good run up.. thinking of what to do now to get the best out of the gearing.. by changing either the front sprocket to 17 or the crownwheel to 46 or am i barking up the wrong tree..

Anyone else running a 175 with Ancilloti BB /30ml dellorto and happy with its performance.. and what gearing are you using.

Thanks
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corrado
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17 x 46 will give you something inbetween the ones you've already tried.
nuttyboy
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im running a series 3 ibar 150 special with 185 head 30mm dellorto. ancilloti exhaust.have same problem flies through 1st 2nd 3rd guttless up any incline in 4th takes ages to wind up in 4th.been told maybe need smaller main jet ?.not sure what gearbox its running prob original one whatever that is .be intresting to find out if it gearing or carb or both :?:
shocky
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can you guys explain why you have just fitted a oversize head or do you mean you have a complete 17/185 top end ?
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soullad
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Far too may overgear their Lambrettas, just as far too many Lambrettas are in my eyes over-carbed.
Fellas, try to listen to what your motor is telling you, and not what yer mates down the pub say it should pull. If its overgeared then try different sprockets until it feels right. Every motor is different.
Of course, jetting, timing, exhaust choice, compression ratio, state of tune, size of carb etc etc all affect performance and therefore gearing, but a simple change of gearing will often bring to life a previously uninspiring motor.
nuttyboy
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hi again mines a 185 ported barrel and head profiled runs at 13bhp on dyno should pull 70mph .running rich at mo.but guttless at ova half throttle on any incline ....carb or gearing ?
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Muttley McLadd
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It's not just bhp you need. You need torque too. Or you'll be stuck with running a low geared bike that needs to be kept at high revs just to keep it moving.
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simplex
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soullad wrote:Far too may overgear their Lambrettas, just as far too many Lambrettas are in my eyes over-carbed.
Fellas, try to listen to what your motor is telling you, and not what yer mates down the pub say it should pull.
Thanks .. dont disagree with you there.. which is why I asked the question on a public forum for examples of others similar setups as a comparison ....
About 6 mnths ago I coupled a 25ml with the Ancillotti on a 175 top end, with a view that it may provide better fuel economy for the daily commute.. originally I used the DL125 gearbox.. but found each gear too short..loads of noise and going nowhere. so upped the box to a standard 200.. also using a typical set up listed on on http://www.smellofdeath.com/lloydy/carb.htm for a 175-standard BB exhaust & there was the 30ml contained within the spec.. I had one knocking about so thought Id give it a try.. if I can run it properly with this set up then perhaps i may be able to work my way back down again..

What i should have asked if anyone knew from experience what dropping from an 18 front sprocket to 17 have over changing the crownwheel from 48 to 47. .. or would one change them both.. this was only to maybe avoid taking it apart several times on my knees on the driveway in fast fading light
jefo1970
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Correct me if I'm wrong mate but isn't the DL(GP) 125 gearbox the same as the 200 presuming you meant a GP200 box! Albeit slightly different 3rd to 4th gear ratios on Indian box.
What front and rear sprockets are you running now, the GP125 runs 15/46 and the GP200 18/47?
What exhaust are you running, 42mm Clubman?


Jefo
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simplex
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jefo1970 wrote:Correct me if I'm wrong mate but isn't the DL(GP) 125 gearbox the same as the 200 presuming you meant a GP200 box! Albeit slightly different 3rd to 4th gear ratios on Indian box.
What front and rear sprockets are you running now, the GP125 runs 15/46 and the GP200 18/47?
What exhaust are you running, 42mm Clubman?


Jefo
Yep.. thats correct..
gearbox is the same but with a 15/46 .. then changed to 18/47 .. which it is currently running.. exhaust is cam lam Ancilloti clubman..
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